We address the quantum estimation of the diamagnetic, or A 2 , term in an effective model of light–matter interaction featuring two coupled oscillators. First, we calculate the quantum Fisher information of the diamagnetic parameter in the interacting ground state. Then, we find that typical measurements on the transverse radiation field, such as homodyne detection or photon counting, permit to estimate the diamagnetic coupling constant with near-optimal efficiency in a wide range of model parameters. Should the model admit a critical point, we also find that both measurements would become asymptotically optimal in its vicinity. Finally, we discuss binary discrimination strategies between the two most debated hypotheses involving the diamagnetic term in circuit QED. While we adopt a terminology appropriate to the Coulomb gauge, our results are also relevant for the electric dipole gauge. In that case, our calculations would describe the estimation of the so-call… …
A quantum is the smallest possible unit of anything, and Quantum Science is the study of these particles and their application. In other words, we know that all matter is made of atoms, but what is the smallest component of an atom and how does it react to stimuli? That deceptively simple explanation is an introduction to a field of science that is exploding into the disciplines of engineering and technology.
The theory of quantum physics has led many to wonder about the nature of matter. Quantum particles seem to react at times like individual particles and at times like continuous waves. This results in some surprising properties.
One of these, superposition, is the ability of quantum systems to include all possible measurements, and only take on certain characteristics when they are measured.
Entanglement is another property of the particles in which the characteristics of multiple particle systems correlate to one another. When you alter one set of measurements, the entire system changes. At the point where these discoveries intersect known developments in information technologies, new opportunities burst open in computing, navigation, sensing, the ability to do simulations and in other areas. This is a rapidly-morphing science that is changing other disciplines as it grows.
Text source: The Computer Science Degree Hub